Thailand was the world's most congested country for traffic in 2016, according to a study released Monday by INRIX Inc.

Drivers in Thailand spent an average of 61 hours stuck in traffic last year, followed by motorists in Colombia and Indonesia with an average 47 hours.

INRIX, based in Kirkland, Washington, aggregates and analyses traffic data collected from vehicles and highway infrastructure. The company said the latest edition of its Global Traffic Scorecard report was based on 500 terabytes of data from 300 million sources.

The company said countries are ranked by a weighted average of their cities' peak hours spent in traffic congestion last year. There are 1,064 cities ranked from 38 countries around the world.

Among cities in Thailand, the study said that out of the 64.1 hours on average which Bangkok drivers spent stuck in traffic last year, some 23% of overall time and an average 33% of their time was spent stuck during peak hours, wasting much fuel in the process.

This was immediately above Caracas and Mexico City, both long known for their horrendous traffic, and which were near the top of the list in the 2015 rankings.

But Los Angeles was the city with the world's biggest rush-hour traffic delays, said the study, with 104.1 hours.

Its Global Traffic Scorecard rated Bangkok the 12th most congested of all cities rated, considerably worse than 30th in 2015.